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BACKGROUND Recent studies have demonstrated that inhibition of CD26 potentiates stromal cell-derived factor-1α (SDF-1α), promotes tissue regeneration, and suppresses the rejection of organ transplants. This study investigated whether the combination of a CD26 inhibitor (CD26i) with granulocyte colony-stimulating factor (G-CSF) and short-term immunosuppressants modulates vascularized composite tissue allotransplant survival in a rodent orthotopic hindlimb allotransplant model. METHODS The hindlimb allotransplantation from Brown-Norway to Lewis rats was divided into 4 groups. Group 1 (controls) did not receive any treatment. Group 2 was treated with short-term antilymphocyte serum (ALS) and cyclosporine-A (CsA). Group 3 was administrated CD26i and G-CSF. Group 4 received a combination of CD26i/G-CSF/ALS/CsA. Each subgroup comprised 10 rats. Peripheral blood and sampling of transplanted tissues were collected for immunological and histological analysis. RESULTS The results revealed that allotransplant survival was found to be significantly prolonged in group 4 with CD26i/G-CSF/ALS/CsA treatment compared with those in the other groups. The interleukin-10 and transforming growth factor-βl levels, the percentage of CD4+/CD25+/FoxP3+ T cells, as well as the levels of SDF-1α expressions were significantly increased in group 4 compared with those in the other groups. Group 4 revealed a statistical increase in the percentage of donor cells (RT1n) expression in the recipient peripheral blood, and the mixed lymphocyte reaction showed hyporesponsiveness of the T cells to donor alloantigens. CONCLUSION The combination of CD26i/G-CSF and short-term immunosuppressants prolongs allotransplant survival by inducing immunoregulatory effects and enhancing the percentage of SDF-1α expression. This immunomodulatory approach has great potential as a strategy to increase vascularized composite allotransplantation survival.

Current understanding of steroid treatments for keloids is in regards to modulation of inflammation, proliferation, and apoptosis, with no in vivo study on the latter. Using a nude mouse model, we investigated whether triamcinolone acetonide (TA) injections induce keloids regression through enhancing apoptosis.Thirty-six keloid specimens (1 × 1 cm) were harvested from 6 patients and separated into sets of 2 from the same patient: no treatment and intralesional TA injection (0.4 mg/mL/kg) at 8 weeks of postimplantation. One set was implanted in each of 18 randomly selected nude mice, which were separated into 3 groups based on time of keloid harvesting after treatment: group A, 2 weeks; group B, 8 weeks; and group C, 14 weeks. Each group had 1 set of specimen from each patient. Histological staining was performed with hematoxylin and eosin stain. Immunohistochemistry staining was performed for human-prolyl 4-hydroxylase (hPH4) and caspase 3 protein, along with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay.All keloid specimens survived, with no noted overgrowth. Hematoxylin and eosin staining revealed dense extracellular matrix and viable fibroblasts, and hPH4 immunohistochemistry revealed strong expression, demonstrating keloid viability. Caspase 3 protein and TUNEL expressions were significantly increased in the treatment versus control groups, demonstrating that TA injections induced apoptosis.Triamcinolone acetonide intralesional injections significantly increased apoptosis in keloids, represented by increased caspase 3 protein and TUNEL expressions, supporting that steroids suppress keloids in part owing to enhancement of apoptosis.

Background Our previous studies demonstrated that adipose-derived mesenchymal stromal cells (ASCs) have immunomodulatory effects that prolong allograft survival in a rodent hind-limb allotransplant model. In this study, we investigated whether the effects of immunomodulation by ASCs on allograft survival are correlated with B cell regulation. Methods B cells isolated from splenocytes were cocultured with ASCs harvested from adipose tissue from rodent groin areas for in vitro experiments. In an in vivo study, hind-limb allotransplantation from Brown-Norway to Lewis rats was performed, and rats were treated with ASCs combined with short-term treatment with anti-lymphocyte serum (ALS)/cyclosporine (CsA) as immunosuppressants. Peripheral blood and transplanted tissue were collected for further analysis. Result An in vitro study revealed that ASCs significantly suppressed lipopolysaccharide-activated B cell proliferation and increased the percentage of Bregs. The levels of immunoregulatory cytokines, such as TGF-β1 and IL-10, were significantly increased in supernatants of stimulated B cells cocultured with ASCs. The in vivo study showed that treatment with ASCs combined with short-term ALS/CsA significantly reduced the B cell population in alloskin tissue, increased the proportion of circulating CD45Ra+/Foxp3+ B cells, and decreased C4d expression in alloskin. Conclusion ASCs combined with short-term immunosuppressant treatment prolong allograft survival and are correlated with B cell regulation, C4d expression and the modulation of immunoregulatory cytokines.

The spatial-temporal distribution characteristics of O

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Real-time aerosol extinction retrieved by Micro-pulse LIDAR and concentrations of PM

A magneto-responsive energy/drug carrier that enhances deep tumor penetration with a porous nano-composite is constructed by using a tumor-targeted lactoferrin (Lf) bio-gate as a cap on mesoporous iron oxide nanoparticles (MIONs). With a large payload of a gas-generated molecule, perfluorohexane (PFH), and a hydrophobic anti-cancer drug, paclitaxel (PTX), Lf-MIONs can simultaneously perform bursting gas generation and on-demand drug release upon high-frequency magnetic field (MF) exposure. Biocompatible PFH was chosen and encapsulated in MIONs due to its favorable phase transition temperature (56 °C) and its hydrophobicity. After a short-duration MF treatment induces heat generation, the local pressure increase via the gasifying of the PFH embedded in MION can substantially rupture the three-dimensional tumor spheroids in vitro as well as enhance drug and carrier penetration. As the MF treatment duration increases, Lf-MIONs entering the tumor spheroids provide an intense heat and burst-like drug release, leading to superior drug delivery and deep tumor thermo-chemo-therapy. With their high efficiency for targeting tumors, Lf-MIONs/PTX-PFH suppressed subcutaneous tumors in 16 days after a single MF exposure. This work presents the first study of using MF-induced PFH gasification as a deep tumor-penetrating agent for drug delivery.

The present study was conducted to clarify the psychophysiological relaxation effects of viewing bamboo on university students. Forty healthy Chinese participants enrolled in this study to clarify the psychophysiological relaxation effects of viewing bamboo. The effects of visual stimulation using a pot both with and without a bamboo were recorded by measuring the student's blood pressure, EEG and STAI. We observed that viewing bamboo plants resulted in significantly lower systolic (female, P0.001; male, P0.001; P0.05) and diastolic (female, P0.001; male, P0.001; P0.05) blood pressures, but no changes in the pulse rate (female, P = 0.09; male, P = 0.07; P0.05) were observed. The results of the EEG analysis indicated brainwave variation (all P0.05) and lower anxiety scores (P0.01) after 3 min of viewing bamboo compared with the control. These findings indicate that visual stimulation with bamboo plants induced psychophysiological relaxation effects on adults.

It is the aim of this research to describe the horizontal well performance in different conditions, this paper firstly introduces 13 dimensionless variables to describe the influence factors of horizontal well performance in bottom water reservoir and calculates the range of all the variations from low to high level by making a statistics of the actual field data of the 23 horizontal wells, then establishes the oil recovery model with response surface method using a 3 level-13 variables Box-Behnken design (BBD) . Based on the evaluation model, single factor sensitivity and interaction analysis between any two factors are carried out. Finally, research on horizontal well in typical bottom water reservoirs indicates that the values calculated by the new evaluation model fit the actual field data, which proves that the evaluation model can provide criteria for the design or optimization of horizontal well development in a bottom water reservoir.

Development of bottom water reservoir with horizontal well can effectively slow down water coning and avoid early water breakthrough in oil wells, which promotes the extensive application of horizontal well in bottom water reservoir. In this paper, literatures about horizontal well are investigated, and the latest research trend is summarized. All factors such as reservoirs, fluid property and production mode to influence horizontal well performance in bottom water reservoir are systematically studied by using reservoir numerical simulation. Based on the calculation results of reservoir parameters of the pilot area, comprehensive analysis to the key factors which affecting horizontal well performance is carried out and the influence degree of various factors on oil recovery is obtained. In a word, the research results in this paper can provide criteria for the design or optimization of horizontal well development in bottom water reservoir.

Severe haze episodes shrouded Beijing and its surrounding regions again during December, 2015, causing major environmental and health problems. Beijing authorities had launched two red alerts for atmospheric heavy pollution in this period, adopted a series of emergency control measures to reduce the emissions from major pollution sources. To better understand the pollution process and emissions variation during these extreme pollution events, we performed a model-assisted analysis of the hourly observation data of PM₂.₅, and meteorological parameters combined with the emissions variation of pollution sources. The synthetic analysis indicated that: (1) Compared with the same period of last year, the emissions of atmospheric pollution sources decreased in December 2015. However, the emission levels of primary pollutants were still rather high, which were the main intrinsic causes for haze episodes, and the unfavorable diffusion conditions represented the important external factor. High source emissions and meteorological factors together led to this heavy air pollution process. (2) Emergency control measures taken by the red alert for heavy air pollution could decrease the pollutants emission by about 36% and the PM₂.₅ concentrations by 11% to 21%. Though the implementation of red alert could not reverse the evolution trend of heavier pollution, it indeed played an active role in mitigation of PM₂.₅ pollution aggravating. (3) Under the heavy pollution weather conditions, air pollutants continued to accumulate in the atmosphere, and the maximum effect by taking emergency measures occurred 48-72 hours after starting the implementation; therefore, the best time for executing emergency measures should be 36-48 hours before the rapid rise of PM₂.₅ concentration, which requires a more powerful demand on the accuracy of air quality forecast.

Two different pollution situations of O₃ and PM₂.₅ during summer in Beijing were analyzed from theperspective of synoptic situations, meteorological elements, precursors, atmospheric oxidation, back-trajectories of air mass and chemical compositions of PM₂.₅. The results showed that the synoptic situations in the pollution situation that O₃ reached middle level pollution and PM₂.₅ maintained low concentrations (O₃high-PM₂.₅ low) could be characterized as northwest gas flow in 500 hPa height and high-pressure rear in the ground. Whereas the synoptic situations in the pollution situation that O₃ and PM₂.₅ both reached middle level pollution (O₃-PM₂.₅ high) could be characterized as westerly gas flow in 500 hPa height and low pressure in the ground. Compared with the O₃high-PM₂.₅ low situation, meteorological elements in O₃-PM₂.₅ high situation could be characterized as stronger southerly winds and higher relative humidity. In the O₃-PM₂.₅ high situation, initial concentrations of O₃ and PM₂.₅ were higher and diurnal variations of PM₂.₅ were more significant, nevertheless, the average concentrations of O₃ were lower than those in the O₃high-PM₂.₅ low situation, respectively. The analysis of precursors, atmospheric oxidation and chemical compositions of PM₂.₅ showed that the accumulation and hygroscopic growth of PM₂.₅ under unfavorable meteorological conditions as well as the regional transport caused by strong southerly winds might be the main factors leading to high PM₂.₅ concentrations in O₃-PM₂.₅ high situation.

Variations of air quality, meteorological conditions and the effect of pollution control measures on particle matter concentrations in Beijing were all analyzed during APEC (from 1st to 12th in November) in 2014 based on the atmospheric pollutant monitoring data, monitoring components of PM2.5, meteorological and remote sensing data and CMB model. The results showed that the average concentrations of PM2.5, PM10, SO2, NO2 were 43,62,8,46 [g.m respectively during APEC and the average concentrations of PM2.5, PM10, SO2, NO2 were decreased by 45%, 43%, 64% and 31% compared to those in the same period of the last 5 years (PM2. was the average of the last 2 years); the concentrations of PM25 at different sites were decreased by 27.4%-35.5%; the concentrations of PM2.5 in the center of city and northern mountainous areas were the lowest, which dropped by 30%-45% compared to those in the same period of the last 5 years while in the southern area the decrement was below 25%; the main component SO4(2-), the substance of the crust, and NO3- were decreased by 50%, 76%, 35% respectively compared to those in the same period in 2013 and the chemical mass balance (CMB) model analysis results indicated that contributions of coal boiler, dust, motor vehicle were 2%, 7%, 30% respectively during APEC; air pollution control measures (coal, dust and traffic management) had a significant effect on reducing pollutant emissions and the pollutant emissions control reduced the concentration peak and delayed the accumulation speed.

PM₂.₅, background concentration at different directions in 2013 in Beijing was analyzed combining the techniques of mathematical statistics, physical identification and numerical simulation (CMAQ4.7.1) as well as using monitoring data of six PM₂.₅ auto-monitoring sites and five meteorological sites in 2013. Results showed that background concentrations of PM₂.₅ at northwest, northeast, eastern, southeast, southern and southwest boundary sites were between 40.3 and 85.3 µg · m⁻³ in Beijing. From the lowest to the highest, PMPM₂.₅ background concentrations at different sites were: Miyun reservoir, Badaling, Donggaocun, Yufa, Yongledian and Liulihe. Background concentration of PM₂.₅ was the lowest under north wind, then under west wind, and significantly higher under south and east wind. Calculated PM₂.₅ background average concentrations were 6.5-27.9, 22.4-73.4, 67.2-91.7, 40.7-116.1 µg · m⁻³ respectively in different wind directions. Simulated PM₂.₅ background concentration showed a clear north-south gradient distribution and the surrounding area had a notable effect on the spatial distribution of PM₂.₅ background concentration in 2013 in Beijing.

Spatial and temporal distribution of SO2 during 2000-2014 was all analyzed based on the SO2 monitoring data that Beijing Municipal Environmental Monitoring Center released and the formation mechanism of a typical air pollution episode in January 2014 was also investigated by combining numerical model CAM(x). Analysis results showed that mass concentration of ρ(SO2) in Beijing in 2014 decreased 69% compared to that in 2000 with an annual gradient from 2000 to 2014 of - 3.5 μg x (m3 x a)(-1). Monthly average concentration of SO2 changed in a U shape curve and from the lowest to the highest, and seasonal variations of SO2 concentrations were as follows: winterspringautumnsummer; concentration of SO2 in heating season was significantly higher than that in non heating season. Annual average concentration of SO2 was lower in northern and western regions while higher in six city area and southern area. Concentrations of SO2 at Shijingshan, Dongsi, Tongzhou monitoring sites were significantly decreased related to SO2 emission reduction measures. During a heavy air pollution process in January 14 - 18th 2014 there was obviously SO2 regional transportation and model simulation analysis based on PAST showed that the contribution of SO2 regional transport to Beijing was 83% with elevated power plants surrounding Beijing accounting for 21% and the four major Beijing power plants contributing about 3.5% to the SO2 concentration during this heavy air pollution process.

Traditional squash method was used to analyze chromosome number and karyotypes of four Scutellaria species in Chongqing Jinyun Mountain Natural Reserve： Scutellaria tsinyunensis, S.yunnanensis, S.franchetiana and S.indica.The result showed that the chromosome numbers were 26 except for S.franchetiana, which had 24 chromosomes.These species were all diploid with metacentric and submetacentric chromosomes.Their karyotypes were symmetrical and primitive.The karyotype formula of S.tsinyunensis is 2n=2x=26=24m+2sm, 1B type, As.k=55.28%; the karyotype formula of S.yunnanensis var.salicifolia is 2n=2x=26=26m, 1B type, As.k=56.11%; the karyotype formula of S.franchetiana is 2n=2x=24=20m+4sm, 2B type, As.k=58.50%; the karyotype formula of S.indica is 2n=2x=24=20m+4sm, 2B type, As.k=58.41%.The results were compared with the reported data of S.baicalensis and S.alaschanica.S.alaschanica is expected to be the most advanced one whereas S.tsinyunensis, and S.yunnanensis var. salicifolia primitive.These results are expected to provide some references to the origin and differentiation of genus Scutellaria.

To analyze the impacts of emissions from fireworks on the air quality, monitoring data of PM2.5, PM10, SO2, NO2 chemical compositions of PM2.5 of automatic air quality stations in Beijing during Spring Festival(February 18th-24th) in 2015 were investigated. Moreover, we also estimated the fireworks on the New Year's Eve produced based on the ratio of PM.5 to CO. Analysis results showed that the concentrations of PM2.5, PM10, SO2, NO2 during 2015 Spring Festival was 116. 85, 184.71, 22. 14, and 36. 27 µg.m-3 respectively, which raised 52. 61%, 92. 41%, - 40. 15%, - 0.46% respectively compared to the same period in 2014; the concentration peaks of PM2.5, PM10, SO2, NO2 at 1 : 00 am on 19th was 412. 69, 541. 63, 152. 73, 51. 09 µg.m-3, respectively, which was increased 19. 02%, 14. 37%, 76. 57%, 11. 35% compared to that of 2014; the concentration peaks at dense population area were significantly higher than that in other districts; fireworks had great influence on the chemical compositions of PM2.5 especially on the concentrations of chloride ion, potassium ion, magnesian ion, which were 18. 85, 66. 72, and 70. 10 times than that in 2013-2014; fireworks resulted in severe air pollution in a short time and the estimated fireworks on the New Year's Eve was approximately 2. 13 x 10(5) kg of PM2.5. Reduction of pollutants during Spring Festival had a positive significant impact on air quality in Beijing.

Biodegradable polymers, such as polycaprolactone (PCL), have been well studied in the application of tissue engineering and drug delivery systems due to their favourable biocompatibility profiles. However, little research has discussed the influence of the molecular weight of these polymers on cell behaviours. Here, PCL films were synthesized using polymers with various molecular weight and the physical characteristics of these films and their effect on cell growth were evaluated. Results showed that the tensile strength and elongation rate of PCL films increased from 1.82 MPa and 95.3% to 2.01 MPa and 741.6% when the molecular weight (Mn) of polymers increased from 40,000 to 80,000. A significant difference in polymer crystallinity was also observed between these formulations. Moreover, we found that prolonged exposure to UV radiation of these films could lead to the breakdown of polymer chains and consequently increased the crystallinity of PCL films with a corresponding reduction in the tensile strength. Using Hs68 human foreskin fibroblasts, PCL films prepared using high molecular weight polymers (CAPA 6800) displayed a higher cell proliferation rate compared to ones prepared using low molecular weight polymers (CAPA 6400 and 6500). In contrast, a higher cell proliferation rate was observed for PCL films made of low molecular weight polymers, especially CAPA 6500, when H9c2 rat heart myoblasts were used. In conclusion, polymer molecular weight can alter the

The weather conditions, atmospheric environmental background and formation mechanism of a heavy air pollution episode in Beijing City from January 9th to 15th, 2013 was preliminarily investigated by combining observed data and the WRF meteorology model. The results showed that the average concentration of PM2.5 was 323 μg x m(-3) from January 10th to 14th; the heavy pollution episode was closely related to the local meteorological conditions; the stable atmospheric circulation pattern provided favorable environmental field for the lasting of this heavy air pollution; small wind speed, high humidity, low PBL, and lasting temperature inversion were the main reasons for this heavy air pollution incident; further analysis showed that contributions of regional transmission to the receptor sites in Beijing were between 53% - 69% and there were obvious secondary conversions and transformations; overall regional transportation played a more important role during this serious air pollution incident; the meteorological conditions played a key role in the formation and destruction of the heavy air pollution, therefore we need to strengthen the study on early warning of heavy air pollution, in order to prevent and control the air heavy pollution effectively.

Ozone concentrations obtained from 35 automatic air monitoring stations in Beijing were analyzed to investigate their temporal and spatial distribution characteristics. A process with high ozone concentration in summer was analyzed. The results showed that ozone maintained relatively high concentration from May to August while in other months, the ozone concentration was at a low level. Overall, the average concentrations of ozone in different stations in a descending order were comparison and regional station, suburban environment evaluation station, urban environmental assessment station and traffic pollution monitoring station. Ozone diurnal variation showed a single peak distribution, the peak of which appeared at 15:00 or 16:00. Ozone concentration showed obvious weekend effect, which meant ozone concentration in daytime of weekend was higher than that in weekday. Ozone concentration was lower in urban Beijing, higher in surrounding counties and the highest in northeast area with more vegetation. A high ozone concentration process occurred in Beijing on June 3, 2013. Under the effect of southwest wind in the afternoon, the concentration peaks of ozone in Yufa, Fengtaihuayuan, Olympic center and Huairou station occurred in order from south to north. Concentration peak of ozone in Huairou station occurred at 20:00 in the night. It could be concluded that significant ozone transmission characteristic was reflected in this process.